Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net cash paid for capitalized interest	$ 30	$ 32
Alabama Power [Member]
Net cash paid for capitalized interest	4	5
Georgia Power [Member]
Net cash paid for capitalized interest	5	6
Gulf Power [Member]
Net cash paid for capitalized interest	0	2
Mississippi Power [Member]
Interest paid	22	17
Net cash paid for capitalized interest	10	18
Southern Power [Member]
Net cash paid for capitalized interest	$ 10	$ 0